This invention is situated within the technical field of medical and surgical products and relates to a protective device for a needle.
In first instance, the invention is intended to be used in combination with a catheter introducing needle or cannula needle, however, in general it is not excluded to use it in combination with other types of surgical needles.
More particularly, the invention relates to a protective device which is capable of avoiding accidental pricking or wounds being inflicted on health staff during the use of the needles concerned.
In case of a cannula needle assembly the operator is inserting the cannula and the needle which is provided in this cannula, by perforating the skin near the patient's vein or artery and introducing the needle and cannula with their tip into said vein or artery. Once the needle is inserted, the cannula remains in position, partially within the vein, while the needle, which has fulfilled its function, is taken out by the operator.
This is the phase during which the sharp point of the extracted needle is dangerously exposed, with a high risk of pricking or wounding the operator.
The operation involving replacing the needle into a protective hood is equally dangerous for the operator replacing it, as numerous specialised studies have shown statistically.
In order to avoid this problem and to guarantee the safety of health staff during their activity, various kinds of protection devices applicable to cannula needles have been developped.
Safety cannula needle assemblies are known, having a protective device allowing that the needle can be retracted within a protective element, which may be part of the assembly itself, whereby the withdrawal is obtained by activating a lever which pushes the needle correspondingly into the protective element, or manually, by manipulating an external handle connected to the needle which can slide along the axis of the protective element, thereby permitting withdrawal of the needle itself.
The main disadvantage of these devices, which are already known to the profession, is the considerable volume of the protective element which may make it laborious and difficult for the operator to use these cannula needles, resulting in that this known system is less practical and versatile.
Another disadvantage of these protective devices, which are already known to the profession, is not only that they are complicated or composed of a large number of parts, but also that they entail risks of not working properly and that high production costs are involved in producing each of the composing parts and in assembling them.
A further disadvantage is that extra operations are necessary compared to unprotected devices, entailing the risk of omissions or wrongly executed operations by the operator.
The profession is also acquainted with protective devices for cannula needles involving the use of a pair of rings linked by a flexible wire. The first ring is fixed to the base of the needle, while the second is fixed to the end of the cannula and is intended to guide extraction of the needle and to contain its point. The mechanism makes the needle slide, during its extraction, through the axial forum of the second ring until its further extraction is stopped by the fixed length of flexible wire. Hereby, the needle arrives with its needle point into one of the rings. The needle, fitted into the ring with its point protected, can be safely pulled out of the cannula with the entire device comprising the two rings and the wire.
The main disadvantage of this device is the considerable encumbrance entailed by the two protective rings and above all by the flexible wire, which can make it laborious and difficult to use the cannula needle, reducing its functional scope.
A further disadvantage of these rings and in general of all the devices known to the profession, is that the patient's body fluids, and sometimes drugs, which may be deposited on the needle as drops or as an adhesive covering, are still accessible and/or that there still is a considerable risk that these fluids or drugs leave the protective device. Shocks may cause them to squirt on the bare skin or into the eyes of the operators or of others standing in the proximity thereof, entailing the risk of infection or contamination.
The main object of this invention is to provide a protective device for needles, more particularly for cannula needles, which allows to considerably reduce the risk of contact with patient's body fluids or with drugs on the needle, and which prevents that an accidental pricking and the causing of wounds may happen, all this by means of a device which is compact, resulting in that it is also easy to use and in that it is very versatile.
A further aim is to provide a protective device that is easy to construct and assemble and hence not expensive.
Furthermore, this protective device ensures maximum protection for the operator during extraction of the needle from the cannula.